Objective: The authors assess whether implementation of work hour limits is associated with a lower prevalence of medical resident burnout. Method: A survey was mailed to medical residents in different medical specialties at one university. Results: Somewhat lower burnout prevalence was reported among residents after implementation of work hour limits compared with the rates prior to the implementation period. The decrease in burnout prevalence occurred primarily among PGY-1 residents. Prevalence of burnout increased with hours worked. Conclusions: Implementing work hour limits appeared to reduce burnout prevalence.